Effects of repeated long-term psychosocial stress and acute cannabinoid exposure on mouse corticostriatal circuitries: Implications for neuropsychiatric disorders.

introductionVulnerability to psychiatric manifestations is achieved by the influence of genetic and environment including stress and cannabis consumption. Here, we used a psychosocial stress model based on resident-intruder confrontations to study the brain corticostriatal-function, since deregulation of corticostriatal circuitries has been reported in many psychiatric disorders. CB AIMS AND

methodsThe investigation presented here is addressed to assess the impact of repeated stress following acute cannabinoid exposure on behavior and corticostriatal brain physiology by assessing mice behavior, the concentration of endocannabinoid and endocannabinoid-like molecules and changes in the transcriptome.

resultsStressed animals urinated frequently; showed exacerbated scratching activity, lower striatal N-arachidonylethanolamine (AEA) levels and higher cortical expression of cholinergic receptor nicotinic alpha 6. The cannabinoid agonist WIN55212.2 diminished locomotor activity while the inverse agonist increased the distance travelled in the center of the open field. Upon CB

conclusionsThe endocannabinoid system had a direct effect on serotoninergic neurotransmission and glucocorticoid signaling. Cholinergic receptor nicotinic alpha-6 was shown to be deregulated in response to stress and following synthetic cannabinoid drugs thus could confer vulnerability to cannabis addiction and psychosis. Targeting the receptors of endocannabinoids and endocannabinoid-like mediators might be a valuable option for treating stress-related neuropsychiatric symptoms.